static void poorMansProfiling_printInnermostFunctions() {
  MultiSet<S> ms = poorMansProfiling_results();
  print("\nTop innermost functions (" + n(ms.size(), "total sample") + "):\n");
  printLines(map(multiSetToMapPopularFirst(multiSetMapKeys(f firstLine, ms)), func(S trace, int count) { "[" + count + "] " + trace }));
}